Marshall Knight


Bahamas Pool & Patio Ltd.

Nassau, New Providence, Bahamas

Leveling the edge: Knight found a similar solution, except he poured the coping using manufactured cantilever-coping forms. He wanted that to be within 1/8-inch of perfect. He poured the coping to slope up as it moved away from the pool, at a rate of 1/2 inch per foot. At the highest point, he formed a 4-inch slot at the back of the coping to make room for the gutter.

The poured-concrete coping was topped with custom-made, 1-by-2-foot concrete tiles, which could be further leveled to perfection.

The deck also was poured of concrete. The 3 feet immediately surrounding the pool was tilted toward the pool at the rate of 1/4 inch per foot. This way, any splash-out that overshoots the gutter will roll back into the pool.

“You can cannonball all you want,” Knight says. “It’ll go over the gutter, up that slope and then run back into the gutter again.”

Crafting the gutter: On his perimeter-overflow pool, Knight chose 4-inch-wide, pre-manufactured, square PVC gutters. The grate came as part of the system. The white product would be clearly visible, but it made sense with the light gray concrete deck and light-finished pool. The gutter came in 10-foot lengths, with connecting sleeves, so it could be customized to the site. The grates were removable, which Knight liked for future cleaning.

Setting the gutter in place served as the third stage of the leveling process. He wanted them to be perfect. When forming the coping, he left a slot at the back to accommodate the gutters. He made the recess about 3/4-inch deeper than the gutter. Afterward, he and his crew could go back, put a layer of thinset at the bottom of the slot and make adjustments until the gutters were perfectly level.

The inside edge of the gutter was set a touch higher than the concrete coping — just enough so the coping tile could be placed level against it. The gutters were secured to the concrete below by drilling approximately 20 holes and threading nuts into the concrete and putting a sealant around it.

Knight dropped 2-inch pipes every 4- or 6 feet throughout the gutter to feed to a trunk line leading to a remote holding tank.

Preventing leaks: Knight used a sealant in the gutter around the penetrations for pipes leading to the holding tank. He also used a marine adhesive sealant underneath the coping, where it meets with the fiberglass rim.


How three fiberglass experts met the challenge:

San Juan Pools of Charleston

Charleston, S.C.

Compass Pools Vic

Melbourne, Victoria, Australia

  • On the Edge
  • Expert advice on creating the perimeter-overflow effect on concrete pools.